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Journal of Systems Engineering and Electronics 2010年第4期21卷 623-628页

作者： Peng wu ming Yang Control and Simulation Center Harbin Institute of Technology Harbin 150001 E R. China

Aimed at the guidance requirements of some missiles which attack targets with terminal impact angle at the terminal point,a new integrated guidance and control design scheme based on variable structure control approach for missile with terminal impact angle constraint is ***,a mathematical model of an integrated guidance and control model in pitch plane is established,and then nonlinear transformation is employed to transform the mathematical model into a standard form suitable for sliding mode control method design.A sufficient condition for the existence of linear sliding surface is given in terms of linear matrix inequalities（LMIs）,based on which the corresponding reaching motion controller is also *** verify the effectiveness of the proposed integrated design scheme,the numerical simulation of missile is *** simulation results demonstrate that the proposed guidance and control law can guide missile to hit the target with desired impact angle and desired flight attitude angle simultaneously.

关键词： guidance terminal impact angle sliding mode control integrated guidance and control linear matrix inequality(LMI).

Tuning the interfacial reaction environment via pH-dependent and induced ions to understand C–N bonds coupling performance in NO3- integrated CO2 reduction to carbon and nitrogen compounds over dual Cu-based N-doped carbon catalyst

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Journal of Energy Chemistry 2025年第1期100卷 273-285页

作者： Tianhang Zhou Chen Shen Zhenghao wu Xingying Lan Yi Xiao College of Carbon Neutrality Future Technology State Key Laboratory of Heavy Oil Processing China University of Petroleum (Beijing) Institute of Materials Science TU Darmstadt Department of Chemistry Xi'an Jiaotong-Liverpool University Department of Mechanical and Mechatronics Engineering and Waterloo Institute of Nanotechnology University of Waterloo Waterloo

Dual atomic catalysts （DAC）,particularly copper （Cu2）-based nitrogen （N） doped graphene,show great potential to effectively convert CO2and nitrate （NO3-） into important industrial chemicals such as ethylene,glycol,acetamide,and urea through an efficient catalytical process that involves C–C and C–N ***,the origin of the coupling activity remained unclear,which substantially hinders the rational design of Cu-based catalysts for the N-integrated CO2reduction reaction （CO2RR）.To address this challenge,this work performed advanced density functional theory calculations incorporating explicit solvation based on a Cu2-based N-doped carbon (Cu2N6C10) catalyst for *** calculations are aimed to gain insight into the reaction mechanisms for the synthesis of ethylene,acetamide,and urea via coupling in the interfacial reaction *** to the sluggishness of CO2,the formation of a solvation electric layer by anions （F-,Cl-,Br-,and I-） and cations (Na+,Mg2+,K+,and Ca2+) leads to electron transfer towards the Cu *** process significantly accelerates the reduction of *** results reveal that*CO intermediates play a pivotal role in N-integrated ***,the Cu2-based N-doped carbon catalyst examined in this study has demonstrated the most potential for C–N coupling to *** findings reveal that through the process of a condensation reaction between*CO and NH2OH for urea synthesis,*NO3-is reduced to*NH3,and*CO2to*CCO at dual Cu atom *** dual-site reduction facilitates the synthesis of acetamide through a nucleophilic reaction between NH3and the ketene ***,we found that the I-and Mg2+ions,influenced by pH,were highly effective for acetamide and ammonia synthesis,except when F-and Ca2+were ***,the mechanisms of C–N bond formation were investigated via ab-initio molecular dynamics simulations,and we found that adjusting the micro-environment can change the dominant side reaction,shift

关键词： pH-dependent micro-environments C–N coupling Dual Cu-based nitrogen carbon catalysts Explicit solvation model Ion stabilizer AIMD

Review of Service Restoration for Distribution Networks

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Journal of Modern Power Systems and Clean Energy 2020年第1期8卷 1-14页

作者： Feifan Shen Qiuwei wu Yusheng xue Center for Electric Power and Energy Department of Electrical EngineeringTechnical University of DenmarkLyngbyDenmark State Grid Electric Power Research Institute NanjingChina

With the rapid deployment of the advanced metering infrastructure(AMI)and distribution automation(DA),selfhealing has become a key factor to enhance the resilience of distribution *** a permanent fault occurrence,the distribution network operator(DNO)implements the selfhealing scheme to locate and isolate the fault and to restore power supply to out-of-service *** an essential component of self-healing,service restoration has attracted considerable *** paper mainly reviews the service restoration approaches of distribution networks,which requires communication *** service restoration approaches can be classified as centralized,distributed,and hierarchical approaches according to the communication *** these approaches,different techniques are used to obtain service restoration solutions,including heuristic rules,expert systems,metaheuristic algorithms,graph theory,mathematical programming,and multi-agent ***,future research areas of service restoration for distribution networks are discussed.

关键词： Distribution networks fault detection fault isolation service restoration self-healing scheme

Study on the flow field uniformity of hydro-floating ship lift combined type hydraulic-driven system based on the residual energy theory

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Journal of Hydrodynamics 2022年第6期34卷 1156-1161页

作者： Bo wu Ya-an Hu Shu xue State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing210029China Key Laboratory of Transport Technology in Navigation Building Construction Nanjing Hydraulic Research InstituteNanjing210029China

The hydro-floating ship lift originally invented in China is a major innovation in the field of navigation *** shaft water levels synchronization of its unique hydraulic-driven system plays a crucial role in reducing the torque of the synchronous shafts and ensuring the safety and stability operation of the ship *** study aims to investigate the muti-shaft water level synchronization and the flow velocity uniformity of the combined type hydraulic-driven *** on the theory of residual energy,a new index m2 proposed in this study is more suitable for evaluating the flow velocity uniformity of the combined hydraulic-driven ***,the critical value of m2=75 is calculated via the results of the scaled physical mode test as the threshold of water flow uniformity,and it provides a basis for determining the reasonable height of the pressure stabilizing chamber.

关键词： Hydro-floating ship lift water levels synchronism residual energy velocity distribution uniformity coefficient

Isoconversional kinetic analysis of decomposition of bastnaesite concentrates with calcium hydroxide

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Journal of Rare Earths 2020年第12期38卷 1361-1371页

作者： Peng Cen xue Bian Wenyuan wu School of Metallurgy Northeastern UniversityShenyang 110819China

Isoconversional methods combined with thermogravimetry were applied to investigate the decomposition kinetics of bastnaesite concentrates with different amounts of calcium hydroxide *** apparent activation energy was calculated,and the results indicate that the overall reaction involves more than one single *** reaction with a lower content(15 wt%)involves another step which denotes the decomposition of newly formed calcium carbonate during *** activation energy increases with increasing amount of calcium hydroxide in the lower range(0-15 wt%).This is due to the resistance of calcium hydroxide to heat and mass transport,However,more calcium can promote the decomposition reaction more effectively and thus reduce the activation *** fitting was performed by fitting the experimental data to Avrami-Erofeev model to determine the reaction model and pre-exponential *** theoretical models were proven to be reliable for kinetic prediction.

关键词： Bastnaesite Thermal analysis kinetics Isoconversional method Calcium hydroxide Rare earths

Order Timing for Manufacturers with Spot Purchasing Price Uncertainty and Demand Information Updating

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Journal of Systems Science and Systems Engineering 2020年第6期29卷 631-654页

作者： Mengchu wu Lijun Ma Weili xue School of Economics and Management Southeast UniversityNanjing 211189China College of Management and Institute of Big Data Intelligent Management and DecisionShenzhen UniversityShenzhen 518060China

In this paper we study the competitive order timing decisions of two manufacturers with demand forecasting updating and uncertain raw material *** can order the raw materials early when the market is highly uncertain with a fixed wholesale price(Contract procurement)or late when the market is less uncertain with an uncertain raw material price(Spot trading).Different from most existing literature,we assume the spot price and the market demand is *** find that in the monopoly setting the manufacturer prefers the contract procurement to the spot trading when the unit wholesale price for the contract procurement is not greater than the expected unit spot price of the raw *** the duopoly setting,we characterize the equilibria of a strategic order timing game in which manufacturers choose when to buy the raw *** find that when the demand during the contract procurement stage and the spot price uncertainty is small both manufacturers prefer the contract procurement strategy and when the demand during the contract procurement stage and the spot price uncertainty is large both manufacturers prefer the spot *** the demand during the contract procurement stage and the spot price uncertainty is high and purchase costs do not decline too severely over time,the unique equilibrium of this game is that one manufacturer chooses contract procurement to order early and the other chooses spot trading to order ***,we find that the correlation of spot purchasing price and the market demand signal during the contract procurement stage will weaken the advantages of spot trading *** the spot purchasing price and the market demand signal during the contract procurement stage are not correlated,manufacturers prefer spot trading under the highly volatile spot trading price,fluctuating demand,and high information precision.

关键词： Procurement order timing competition uncertainty game theory

Generalized Thermal Instability Criterion of Black Hole Accretion Disks

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Chinese Physics Letters 1998年第7期15卷 542-544页

作者： wu xue-bing Beijing Astronomical Observatory Chinese Academy of SciencesBeijing 100012 Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100080

The conventional thermal instability criterion cannot be applied to the advection-dominated accretion disks around black holes where the radiative cooling is insufficient to balance the viscous *** surface density change associated with the temperature perturbations,which was usually neglected in deriving the conventional criterion,was recently shown to be much significant in the advection-dominated *** both advection and surface density change,a generalized thermal instability criterion is *** applying it to the optically thin and optically thick advection-dominated disks,it is found that the former one is thermally stable and the latter one is thermally unstable against short wavelength perturbations,which agrees well to those found recently by both analytic and quantitative stability analyses.

关键词： criterion perturbations Criterion

Hot-cracking susceptibility and shear fracture behavior of dissimilar Ti6Al4V/AA6060 alloys in pulsed Nd:YAG laser welding

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Chinese Journal of Aeronautics 2021年第4期34卷 375-386页

作者： Xin xue Xinyong wu Juan LIAO School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350116China Fujian Nebula Electronics Co. Ltd.Fuzhou 350015China

Laser welding of dissimilar titanium/aluminum alloys has been employed at an increasing rate,particularly in the aerospace industry,owing to its advantages in terms of current design flexibility and fuel/cost *** major problem with dissimilar Ti/Al welds arises from the difference in the thermal expansion and contraction of the two metals,which leads to hot-cracking susceptibility and the mitigation of the mechanical property after *** the present study,pulsed Nd:YAG laser welding of Ti6 Al4 V and AA6060 has been ***-cracking susceptibility in the heat affected zone and the shear fracture behavior of the lap joints were investigated through microstructural characterization and mechanical *** results indicate that the hot cracking tendency can be reduced by increasing the pulse peak power(7.5–8.5 kW)and the laser point diameter(0.8–1.0 mm)with specific pulse duration and *** alternative control strategy for less hot cracks in the Ti/Al lap joint can be to increase the weld width and decrease the cooling rate during *** shear fracture of the Ti/Al lap joint is likely to occur along the lower side path of the weld interface with decreasing weld surface collapsed amount and increasing aluminum base metal melt depth.

关键词： Aluminum alloy Hot-cracking susceptibility Pulsed Nd:YAG laser welding Shear fracture behavior Titanium alloy

First in situ UV profile across the UTLS accompanied by ozone measurement over the Tibetan Plateau

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Journal of Environmental Sciences 2020年第12期32卷 71-76页

作者： Jinqiang Zhang Xiangao Xia xue wu Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing210044China University of Chinese Academy of Sciences Beijing 100049China

Ultraviolet radiation(UV) and ozone can greatly affect human health and the Earth's ecological environment. By deploying a UV radiometer aboard a stratospheric balloon released at Qaidam(QDM) during the Asian summer monsoon(ASM) period in 2019, we provided in situ measurement of the UV profiles from the surface to the upper troposphere and lower stratosphere over the Tibetan Plateau(TP), China, for the first time. Based on two in situ UV profiles accompanied by four ozonesonde measurements, this study exhibited detailed variations of downwelling UV and vertical ozone distributions over the TP during the ASM period. The UV differences between the surface and stratospheric balloon flight altitudes were 16.7, 15.8, 12.6 and 18.0 Wm^-2 during the four ozonesonde launches. Due to the diurnal variations in photochemical production and the stratosphere-troposphere exchange, the integrated ozone columns below 30 km ranged from 184.4 to 221.6 DU from four ozonesonde measurements. A positive correlation between UV attenuation and ozone column was exhibited under low cloud cover and clear sky conditions. The results of this study are expected to improve our understanding of UV and ozone properties, as well as their potential effects on terrestrial ecosystems and living environments over this significant plateau.

关键词： Ultraviolet radiation Ozone In situ measurements Asian summer monsoon Tibetan Plateau

单/多克隆抗体在肾移植急性排斥反应中的临床应用研究

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西北国防医学杂志 2006年第5期27卷 332-335页

作者：潘晓鸣薛武军田普训丁小明西安交通大学医学院第一附属医院肾移植科陕西西安710061

目的:探讨应用抗淋巴细胞单克隆/多克隆抗体治疗肾移植术后急性排斥反应的效果、安全性和副反应等。方法:我中心施行同种异体肾移植术后对激素冲击治疗不敏感的急性排斥患者43例,分为两组,分别给予单克隆抗体OKT3和多克隆抗体ALG治疗,... 详细信息

目的:探讨应用抗淋巴细胞单克隆/多克隆抗体治疗肾移植术后急性排斥反应的效果、安全性和副反应等。方法:我中心施行同种异体肾移植术后对激素冲击治疗不敏感的急性排斥患者43例,分为两组,分别给予单克隆抗体OKT3和多克隆抗体ALG治疗,并对治疗效果、安全性和药物副反应等进行分析。结果:ALG治疗25例,排斥逆转16例,治愈率64%;OKT3组18例,排斥逆转15例,治愈率83.3%;两组有显著性差异(P<0.05)。结论:单/多克隆抗体作为肾移植术后排斥反应的治疗用药,临床效果肯定.可使一部分患者避免因排斥反应丧失移植肾。但同时它们进入人体能引起首剂综合征等很多副反应,应当引起重视。OKT3治疗耐激素性急性排斥反应效果优于ALG。

关键词：肾移植急性排斥抗体